The use of concentric wheels for assisting the user in astrological evaluations are known per se. U.S. Pat. 3,992,787 to Lynch, for example, illustrates one version of using wheels and indicators for rapid comparison of the astrological criteria associated with individuals. The Lynch device employs one wheel divided into each of the signs of the Zodiac and a second wheel for designating various times of day. A spoked wheel is positioned between the other two wheels. The relative movement of the three wheels will provide information concerning aspects of the user's life.
The use of the device as taught by Lynch requires the employment of an ephemeris, which is a table of values specifying an angular position and planetary sign for the time of birth of the individual in question. Certain calculations must also be made based on the ephemeris tables.
Other known prior devices require the provision of the time of day of birth of the user for performing the necessary evaluations or are otherwise unnecessarily complex.